The British-American measurement system or Imperial System converted to the Metric System.
Some examples of lengt measurements
1 inch = 2,54
cm
1 cm = 0,3937
inch
1 mm = 0,03937 inch
6
pounder = 4,1 cwt = 35mm = 3,5cm
13
pounder = 9 cwt
18 pounder = 12,4
cwt = 3,5 inch = 8,8 cm = 88 mm
4 inch = 10,1cm
5,9
inch = 150 mm = 15 cm
6 inch = 152
mm = 15,2 cm = 26 cwt
8 inch = 200
mm = 20 cm
9,2
inch = 133 mm = 23,3 cm
11,8
inch = 300 mm = 30 cm
15 inch = 380 mm = 38 cm